ghetto way number 2
take the bullet your going to use and drop it into the chamber, with a peice of dowling give it a light tap into the bore,
take the peive of dowling and run it down your barrle from the muzzle untill it touches the tip of the bullet, with a pencil mark where the dowling exlise the barrel,
tap the bullet back out,
reintall the bolt and closee it, run the dowl back down the bareel and into the bolt face, mark where it exits the barrel again
take your calipers and messure the 2 lines (the thinner you make the lines the more accurate this will be)
this is now the max COAL, on the calpers make the messurement ,015" smaller (or how ever far you want to be off the lands) now useing THE SAME bullet, set up your dies so the OAL matches what you have with the calipers...
total cost = about a buck for the dowling from your hard wear store